Tube building method and apparatus



Dec. 26, 1933. H. D. STEVENS TUBE BUILDING METHOD AND APPARATUS 3 Sheets-Sheet l Filed Jan. 20, 1931 INVENTOR JrfVf/vs.

ATTORNEYS,

Dec. 26, 1933. H D STEVENS 1,941,114

TUBE BUILDING METHOD AND APPARATUS Filed Jan. 20, 1931 5 Sheets-Sheet 2 ATTORNEYLY,

H. D. srEvENs 1,941,114

TUBE BUILDING METHOD AND APPARATUS Filed Jan. 20, 19251 3 Sheets-Sheet 3 Dec. 26, 1933.

|NVENTOR /z/o/wcf 5' rfvf/vs.

ATTORNEYJ` 45 tweenV the, ears V1,2.

Patented Dec. 26, 1933 I l D l 1,941,114

TNT ortica) l .TUBE BUILDING METHOD AND APPARATUS Horace D. Stevens, Akron, Ohio, assigner to .The

Firestone Tire& Rubber Company, Akron, Ohio,

a corporation of Ohio Application January 20, 1931. Serial No. 509,927

' 16 claims. (o1. 154-14),

This invention relates to tube-building methe The rollers 14, 20 `are adapted to support and n ods and apparatus, and more especially it relates to procedure and mechanism forapplying, Yin an improved manner, a longitudinally extending strip of reinforcing material comprising rubber to avtube of unvulcanized rubber in the manufacture of reinforced rubber tubes, such as puncture-proof innerftubes for pneumatic tire casings. The chief objects of theinvention are'to avoid strain and distortion of the tube structureV durf ingrythe application of the reinforoi'ngstrip; substantiallyvto obviate creeping ofthe tube onv its support by reason of the pressurer applied to attach the reinforcing strip; to prevent such creep` ing of the tube as may occur from being cumulative in the entire tube; and to provide an im-r proved' method and improved apparatus for atu-V taining the foregoing objects. A more speciic' object is tol provide automatic mechanical means *0 for stitching or adhesively pressing' a reinforcing strip to a tube of unvulcanized rubbercomposition. Ofjthev accompanying Vdrawings: Y l Figure 1 is a frontelevation of Aapparatus ern-v b'odying and adapted to carry out the inventionin its preferred form, andthe work therein, part of the'latter being broken away; y, Y

y Figure 2 is a side elevation of the apparatus shown in Figure 1, the work'being'shown in sec- Figure 3 is a section,` on a larger scale,

on the line 3-3 of Figure'Z; and 1 l AFigure 4 is a rear elevation, on a larger scale,

s, of the work supporting and driving mechanism.

Referring to the drawings, l0 is a vertical post K or I-beam whichY is suitably supported at its respective ends (not shown), and at an intermediate height support's a shelf V11 which carries the work supporting and driving mechanism; At

.40- ones'ide the shelfll isformedadjacent its front and rear with respective upstanding ears 12, A12 vwhich 'comprise journals` `for a horizontal shaft 13, Vand the latter carries'a centrally Ygroove'd kor Y waisted roller 14 whichis secured Vthereon vbe- VThe 'other vside of the shelf 11 carriesV an extension 15 which is adjustably Asecured to Avthe shelf by bolts 16, ,'16 which 'pass through'respective slots 17in the extension.v The overhanging endV of'the'extension 15 isgformedY atfro'nt and rear with respective upstanding ears'18',"18 which comprise journalsfor a shaft 19,v and the Alatter carries afcentrallygrooved or waisted'roller 20 which is identical with the roller 14 and disposed 55' parallel thereto.

vided at one end with a ratchet 26 Which'is en -1 verticallyY reciprocable rod 31.5 Up and down feed thework whichfis shown hereinras a tubel ,of unvulcanized rubber'composition 21n1o11nted` upon an arcuate mandrel 22, and having a 1ongitudinally extending reinforcing strip 23`of unvulcanized rubber, and other constituent materialif desired,'lightly attached to its outer periphery, the respective lateral marginal portions f of the strip 23 being u nattached.,` Althoughpthe work vis not shown in Vits entirety, it willbepunderstood that the mandrel 22 is of the usualv ar-f .cuate typeY having spaced-apart ends to permit mounting andrremoval ofthe work. If desired,

a bracket 24 may be mounted; upon the shelf- M extension 15 between the'rollers 14, 20 as a sup.- 70" port for .a thirdwaisted roller 2.5 rwhichengages the work between the two `aforesaid rollers andv prevents pendulous movement of thewcrk `upon the rollers 14', 20as an axis. 1

' f The rollers 14, 20 are adaptedltofeed the work 755 A' v intermittently in the direction "indicated by. the arrow in Figure l, and for driving'psaid rollers the 1 shaft 13 is extended beyond its, journals and pro-7` gaged hy' a` feedfpawl' 27 mounted in one end 80-l of a lever 28 that 'is journaledion said` shafty 13, the otherend of` the lever 28fcarrying a roller29 that is engaged'by acollar 30 mounted upon a movement of the collar 30 'rocks the lever v28 through an are defined bythe full line and broken line positions of the lever kas shown in Figure 4 to eilect intermittent rotary movementof the roller 14, and retrogre'ssive movement of the ratchet n 26 is prevented'by a stop-pawl 32 which isv mount- 30" edupon the post 10 and engages the ratchet. A The rod 31 extends kthrough the shelf j; 11, and the collar 30,@which is above the shelf, limits the downward movement of the rod 31'," K The 4other end ofthe 'shaft 13 is providedwith a sprocket 33 that is connected by a sprocket chain 34 with a sprocketl 35v mounted upon the adjacent` end of the shaft 19, for driving the roller 20 in the same direction at the #same speed as the roller 14. Mounted upon lthe opposite end of the shaft 19 is a brake-drum 36 which is engaged by a brlake-bandy 37y for preventing over-run of? the rollers`142f20 at 'the end of their work-feedingv movements.- One 'end'of thebrake-band is lix- .e'dly secured to a stud `38 which extends laterally 105 I from an upstanding ear 39 formed on ,they shelfV ll, and the other end of the brake-band is connected to one end of a tension spring 40, the other end of which is attached to a stud 41 projecting from av bracket 42 that is mounted upon the post 110 10. A guard 43 is mounted over the sprockets 33, 35 and the sprocket chain 34.

Mounted upon opposite sides of the post 16, at an elevation somewhat above the work, are respective guide-plates 44, 44, which extend beyond the front of the post and are formed thereat with vertical slideways 45, 45 for a reciprocable slide 46. Theslide 46 is reciprocated by a motor 47 that is mounted in an elevated position upon a shelf 48 supported from the post 10, the motor driving through a reduction-gear device `49 to a crank 50 that is connected by a link 51 to the upper end of the slide 46. Y

Projecting forwardly from the slide 46 is a web or rib 52. and journaled on one lateral face thereof at 53, is a pair of arms 54, 54 which extend downwardly and cross each other, the free ends of said arms being provided withgrespective presser rollers 55, 55 which are normally disposed in abutting relation above the work, and on opposite sides of the medial plane thereof, as is shown in Figure 2. Also journaled at rants or gear sectors 56', 56 which are meshed with each other and pinned or otherwise secured to the respective arms 54. One of the gear sectors 'is provided with a radial lever arm 5'? which has its free end connected to one end of a tension spring 58, the other end of the latter being connected to an adjustable stud 59 carried by a bracket 60v which is mounted upon the web 52. The arrangement is such that the spring 58 normally holds the arms 54 in the position in whichtheir end-rollers 55 abut each other, and' yieldingly resists spreading apart of the free ends of the arms.

Projecting from the opposite side of the web 52 is a bracket 61,v and secured to the web and extending upwardly therefrom is4 an arm 62 which has its upper end bent at right angles to provide a bracket 63, which bracket is in vertical alignment with the bracket 61'. Each bracket 61, 63 is formed with itwo apertures, the apertures in one bracket being axially aligned with those of the other bracket, and slidably mounted in said apertures is a pair of parallel', vertical rods 64, 64 upon the lower end of which is a presser-foot 65.

' The upper end of eachrod 64 is threaded to receive a pair of nuts 66 which are positioned above the bracket 63. Between the brackets 61, 63 each rod 64 carries an adjustable collar 67, and a compression spring 68 is mounted upon each rod between the collar 6'?y thereon and the bracket 63. The arrangement is such the presser-foot 65,y which has an arcuate, work-engaging bottom face, is periodically applied yieldingly to the outer peripheral portion of the work as the slide 46 is reciprocated.

The reciprocable rod 31 that actuates the work-feeding mechanismhas its upper end slidably mountedl in an apertured bracket 69 (see Figure 3) which is mounted upon the upper edge of; the slide 46, and a collar '70 is mounted upon the rod above sa-id bracket 69. The lower end of the rod 31l is connected to one end of a tension spring 7l, the other end of which is connected to any suitable stationary member (not shown). The arrangement is such that the work is. intermittently indexed or fed forward a determinate distance in timed relation to the reciprocating movement of theslide 46.

In; the operation of the apparatus, the slide 46 being in the elevated, inoperative position shown in full lines in Figures 1 and 2, a mandrel 22 with. an unvulcanized tube 21 and reinforcing strip 23 thereon is mounted upon Vthe grooved rollersr 14, 20` and 25, one end portion of the man- 53, 53'are respective quaddrel resting upon the roller 14 so that the pressing down of the reinforcing strip 23 will be initiated at one end thereof. rlhe motor 47 is then set in motion and the apparatus automatically applies rolling pressure to the reinforcing strip in the direction toward its lateral margins in successive abutting or overlapping Zones longitudinally of the work as the latter is intermittently indexed in timed relationk to the application of the presser rollers.

As the slide 46 moves downwardly, the presser-foot 65 comes to rest upon the crown or medial Zone` oftheV strip 23, and is yieldingly pressed thereagainst by the springs 68 as the latter are compressed by continued downward movement of the slide; The presser rollers 55 upon being urged against the crown of the strip 23, are forced apart, their supporting-arms 54 turning on their pivots 53 against the tension of the spring 58, which thereby constantly urges the presser-rollers against the surface of the strip 23 as they move toward the lateral margins thereof. At the lowermost position of the vslide 46 the vrollers 55 are in the broken line positions shown in `Fig-V ure 2, the collar 30 of the rod 31'is resting uponI the shelf 1l, as is shown in broken lines in Figure 4, and the bracket 69 of the slide is positioned well below the collar 7l)V cn the rod 31.

Upward movement of the slide 46 restores the presser-foot 65 and the presser-rollers 55 to their normal inoperative positions above the work, and near the peak of the upward movement of the slide the bracket 69 engages the collar '70 Von the. rod 31 and raises the latter, against the tension of the spring 7l, with the result that the worksupporting rollers 14, 20 are rotated through vSi determinate angle throughY the agency of the pawl 2'? and ratchet 26. Thus the workis fed" circumferentially and an unpressedY region there- Vof is presented. to the presser-foot and-presser The apparatus is substantially automatic. in

its operation, requiring onlyA manualY mounting and removalV of the work. The apparatus produces work of superiorV quality and accomplishes4 the other advantages. set. out, inthe-foregoing statement of objects.v Y

Modification may be resortedto within the scope of the appended claims which are not limited wholly to the specific construction shown 'or exact procedure described.

What is claimed is: 'i l. The method of building ytubes which comprises fabricating the body structure thereof, and then compacting the sarneby applying pressure thereto in the direction transversev to the longitudinal axis of the tube while the latter is stationary. 2. The method of building tubes which comprises fabricating the body structure thereof, and then compacting succeeding regions of the same in the longitudinal direction by pressure applied in the direction transverse to the vlongitudinal axis of the tube while the latter is stationary.

3. rEhe method of building tubes which comprises fabricatingthe body structure of the tube, and then compacting the same by applying rolling-pressure thereto while the tube is stationary; starting on one side of the tube and progressing in opposite directionsv Vtherefrom transverselyof the longitudinal axis of the tube.

4. A method as definedy in claim 3 inY which the. pressure is applied in succession to adjacent or overlapping regions longitudinally of the tubi'e.

5. The method of making rubber tubes which comprises mounting a strip of reinforcing material on the tube longitudinally'y thereof, applying pressure to the'middle of the strip, and concurrently applying rolling pressure to the striptoward its respective lateral margins.

`6. The method of making rubber tubeswhich comprises feeding the tube longitudinallystepby-step, and applying compacting pressure to entire transversely disposed regions ofthe tube as it is so fed.

7. A method of making rubber tubes as defined in claim 6 in which the compacting pressure is applied to the tube during the intervals that it is stationary between successive forward steps'.

8. The method of making tubes which comprises applying a stripof 'reinforcing material longitudinally of a tube,.intermittently feeding the assembled structure longitudinally, and applying rolling pressure to the reinforcing strip transversely ofthe feed of the tube at determinate time intervals. I

9. Tube building apparatus comprising means ing pressure theretoV during the intervals that is stationary.

12. Tube building apparatus comprising means for supporting and longitudinally. feeding an arcuate tube structure by engagement with the I,innerperiphery thereof, vand reciprocating tubevpressing'means 'comprising a roller having its axis substantially parallel to the feed of the tube Y operatingagainst the outer peripheral portion of the tube'structure.

13. Tube building apparatus as defined in claim 12 in which the tube structure is intermittently,y fed, and the'pressing means is so convvstructed as vto reciprocate in timed relation to the feed of the tube.

, 14. Tube building apparatus comprising means for supporting a tube structure, a reciprocable slide movable toward and away from the tube, and tube-pressing means on said slide adapted l concurrently tov engage and press the tube structure on opposite sides of a plane vpassing through the axis of the tube. y

15. Tube building apparatus comprising means rfor supporting a tube structure, 'a reciprocable slide movable toward and away lfrom the tube, a pair of yarms pivoted onsaid slide, presser-r rollers on the ends of said armsadapted to en-v gage the tube, the pivots of said arms being so arranged that the free endsof the arms spread` apart ,when the presser-rollers are forced against the. tube, -and yielding meansy resisting saidj spreading apart Vmovement of the arms.

16. Tube 'buildingvapparatus comprising means for supporting an arcuate tube `structure from.v4 the inner periphery thereof, 'a reciprocable slide movable substantially radially of the `tube structure, and tube-pressing mechanism carried by` said slide adapted to engage the tube structure on the outer periphery thereof andto move in opposite directionstransversely of the tub'e'exerting yielding pressure thereagainst; Y

HORACE D. STEVENS. 

